Method for forming semiconductor device structure with conductive line

A method for forming a semiconductor device structure, comprising:

• forming a first mask layer over a dielectric layer, wherein the first mask layer has a first trench and a second trench, and the first trench has a first inner wall and a first bottom surface;
• forming a second mask layer over the first inner wall, wherein the second mask layer has a third trench in the first trench and exposing the first bottom surface, the third trench is narrower than the second trench, and the third trench and the second trench are respectively over a first portion and a second portion of the dielectric layer;
• forming an anti-bombardment layer over a first top surface of the first mask layer and a second top surface of the second mask layer, wherein the second mask layer and the anti-bombardment layer are made of different materials;
• removing the first portion, the second portion, the first mask layer, the second mask layer, and the anti-bombardment layer to form a fourth trench and a fifth trench in the dielectric layer, wherein the fourth trench is narrower than the fifth trench;
• and
• forming a first conductive structure and a second conductive structure respectively in the fourth trench and the fifth trench.

A method for forming a semiconductor device structure, comprising:

• forming a first mask layer over a dielectric layer, wherein the first mask layer has a first trench and a second trench, and the first trench has an inner wall and a bottom surface;
• forming a second mask layer over a first portion of a top surface of the first mask layer and the inner wall, wherein the second mask layer exposes a second portion of the top surface, the first portion and the second portion are respectively adjacent to the first trench and the second trench, the second mask layer has a third trench in the first trench and exposing the bottom surface, and the third trench and the second trench are respectively over a third portion and a fourth portion of the dielectric layer;
• removing the third portion, the fourth portion, the first mask layer, and the second mask layer to form a fourth trench and a fifth trench in the dielectric layer, wherein the fourth trench is narrower than the fifth trench;
• and
• forming a first conductive structure and a second conductive structure respectively in the fourth trench and the fifth trench.